Why: Peregrine Falcon populations have undergone a remarkable turnaround. In the early 1900s there were thousands of these birds nesting throughout wild places in the United States. However, serious threats conspired to undermine the stability of these populations. Persecution by humans and, most crucially, the introduction of pesticides such as DDT contributed to the severe decline of peregrine numbers. By 1965 they were completely extirpated in eastern North America.

Today, thanks to restrictions on the use of DDT, legal protection that bans the persecution of raptors, and an immense reintroduction effort by the Pennsylvania Game Commission and many others, peregrine populations have increased. Now these remarkable birds once again grace Pennsylvania’s skies and may be seen nesting on building ledges and other sites in urban settings, as well as at natural cliff sites. Peregrine falcon populations continue to recover, but are still in need of human assistance.

The Peregrine Falcons in Pittsburgh used to be the only peregrines known to breed in the western part of Pennsylvania. These birds have been breeding here since 1991 and at least one Pittsburgh nest has produced young every year since then. They are helped by preparation and maintenance of the nest site, careful observation, and the good will and support of building managers. In recent years several pairs have begun breeding on bridges over rivers throughout our region!

Project Description and Current Status: The Peregrine Falcon was one of the first species listed as Endangered under the U.S. Endangered Species Act of 1974. Recovery for the species has gone so well that it was removed from this list in 1999. However, peregrine populations in the northeast have recovered more slowly and the species is still listed as Endangered in Pennsylvania and several other states. In 2003 Peregrine Falcons were found breeding on cliff sides in Pennsylvania, marking the first occasion since the 1950s that the species has bred in a natural setting in the state.

The Pittsburgh nest sites are especially good for falcon breeding because they are on tall buildings with restricted site access, there are few predators, there is little reflective glass in the area, and because of the goodwill of the local building management.

At each site a custom-made nest box was designed out of weather-resistant lumber and red cedar. The bottom of each box is filled with pea-sized gravel. Falcons do not build their own nests, and our Pittsburgh peregrines create a shallow depression in this gravel where they lay their eggs.

Peregrine Falcons lay approximately 3-6 eggs in March. These eggs are incubated primarily by the female, with the male providing food during this period. Young peregrines fledge about 6 weeks after hatching and within a few weeks are no longer found with their parents. Peregrines feed almost exclusively on small to medium-sized birds, usually caught in mid-air. Diet of these remarkable birds is often determined by local prey availability.

The first regional Peregrine Falcon nest box was installed on the Gulf Tower in 1991, through a partnership established by the Western Pennsylvania Conservancy and the building management. When young were produced there and at City Hall in Philadelphia in 1991, these sites became the first known building nest site for peregrines in Pennsylvania in the post-DDT era.

In 2002, funding provided by the Pennsylvania Game Commission allowed the Western Pennsylvania Conservancy to build and install a second box at the Cathedral of Learning. The boxes were both readily accepted by pairs of wild peregrines and nesting has occurred at each site every year since the boxes were installed.

The Pennsylvania Game Commission bands the young birds with coded leg bands, which allows for the identification of individual birds.

Recent Results: Since the nest site at the Gulf Tower was installed in 1991, 55 Peregrine Falcon chicks have hatched and fledged. The nest box at the Cathedral of Learning has produced 18 peregrine falcon chicks since its installation in 2002.

The Peregrine Falcon is listed as a Pennsylvania Endangered species, which makes the excellent productivity at these nest sites instrumental in increasing peregrine population size. Some peregrines hatched in Pittsburgh have gone on to breed at other locations, including Cleveland, Ohio, and Niagara Falls, New York.

Current Goals:

In March 2008 the National Aviary began hosting Pittsburgh FalconCam, a live streaming web cam of the Peregrine Falcon nest at the Cathedral of Learning on the University of Pittsburgh campus. We are also hosting a downtown Pittsburgh nest web cam in partnership with Point Park University.

The National Aviary, in collaboration with a number of interested organizations and private citizens, is managing the two nest boxes in Pittsburgh.

When chicks are ready to fledge, they are banded. This is a collaborative operation between the Pennsylvania Game Commission, together with staff from the National Aviary and building management.

Next Steps: The National Aviary continues to seek funding to expand this project, putting cameras in nests of other birds in the Pittsburgh region – both in the wild and at the National Aviary. In addition, our educational programs will increase their focus on Peregrine Falcons and other birds of prey.

This project is currently funded by the National Aviary. For many previous years it was supported by the Western Pennsylvania Conservancy. All parties appreciate the assistance in managing the Cathedral of Learning and downtown nests.

For More Information:

US Fish and Wildlife Service details on the conservation status of the Peregrine Falcon.

Pennsylvania Game Commission information on Peregrine Falcons in Pennsylvania: here and here.